Gastric mucosal cells from the mouse stomach isolated and separated into various cell type will be studied by electron microscopy and histochemistry as well as by some biochemical and physiological parameters. The cellular localization of carbonic anhydrase in isolated cells will be studied in conjection with the biochemical demonstration of this enzyme. Further work on the enrichment of isolated gastrin cells will be undertaken to determine more physiological and features of these cells. Oxygen consumption studies on isolated cells as influenced by various metabolic inhibitors and secretogogues will be explored in greater detail. Continued efforts to improve methods of cell isolation so that its surface properties are not greatly disturbed or allowed to recover will be studied by employing electron dense markers such as ruthenium red or rationized ferritin. BIBLIOGRAPHIC REFERENCES: Forssmann, W.G., S, Ito, J. Metz, L.M. Lichtenberger, V. Hemstoedter, L.R. Romrell, and H. Billich. Studies of isolated and separated cells: G Cells of the Pyloric antrum and exocrine pancreatic cells. In Hormonal Receptors in Digestive Tract Physiology (S. Binfils et al., eds.), Elsevier, Amsterdam. 1976. Metz, J., W.G. Forssmann, and S. Ito. Exocrine pancreas under experimental conditions. III Membrane and cell junctions in isolated acinar cells. Cell Tiss. Res. 1977.